Yes, that's chicken heaven - lots of space and a good-sized run that you can get into without crawling! You might consider covering the roof of the run, as otherwise the floor will get horribly muddy when it rains. Also, it would prevent redmite being shaken off from the feathers of wild birds in the tree above, or perching on the run roof. As it's got a good pitch to it, monotex tarpaulin from Bradshaws Direct would do the job, or for a more permanent fix, try corrugated plastic roofing panels, either in green or clear. A gutter will also be helpful to take the runoff, as otherwise rain will blow in under the eaves and make most of the floor wet.
It would also make it easier and more pleasant to keep the run floor clean and dry if you first covered it with permeable weed proof membrane, well pegged down all round, and then added 3-4 inches of dry bedding such as Aubiose, which is shredded hemp, highly absorbent, easy to poo pick, and the results go straight on the compost heap or as mulch round established shrubs in winter. Aubiose is sold for horse bedding so you may be able to collect a couple of bales from a local stables and avoid postage costs, which are high. You can use it in the nest boxes and coop floor as well. there are other alternatives, often available from local country stores etc. Some people use shredded bark or wood chippings, but these are less absorbent and much harder to keep clean, also wood chippings may bring redmite into the run. If you just leave the floor as earth with no roof, it will become a nasty swamp when this lovely dry spell ends.
The membrane will stop them digging earth up into the bedding, so it doesn't get dirty from below, and you can pick up the poo which descends from above every day. Get a membrane a bit bigger the the floor size and tuck it in all round before pegging it down, it will then last for many years. Also give them a dustbath - a large deep container with sand and/or earth, so they can dig there, rather than on the run floor, when they are shut in. With a good-sized run like yours, and with exbatts, there will be perfectly happy, and safe, in the run for all the time you can't be actually with them in the garden, and in winter this will be nearly all the time. Just provide some kind of greens each day they can't go out - they may take a while to get to eat them as this will be quite new to them.
Does that lovely big tree give them shade? Chickens can stand cold conditions but wilt when it's hot and sunny, so if the tree does the job that's fine, but if the run faces south you may need to fix something like willow screening round the exposed parts. Willow is really good at providing filtered shade in summer and wind screening in winter when gales are blowing - they also hate windy conditions.

Hey Marigold, you must be pyschic. Hubbie has been adjusting the run and the coop. Roof has been covered (we previously had a tarpaulin on at night) and some slabs put at the far end of the run as it gets hot in summer and assume would be sludgy in winter. Run is being extended further, so it has a run outside the main run, this one won't be covered and they will only be let in there when we are at home and when the weather is good. Pics will follow soon.

They've had a little freedom these past 3 days and haven't attempted to fly or escape. The only odd thing is that they lay their eggs on the floor of the coop, not in the nest boxes, so this is also going to be adjusted, as on research, it might be it isn't high enough to sit in comfortably.

The big tree is covered in a form of ivy and provides all year round shelter, they love it behind there as there's lots of nice dry soil. I've watched them digging big holes and sleeping in there. They're quite amusing to watch and have lovely temperaments.

Thanks again for good advice. I think I will also get membrane for the pen floor when the weather becomes poor. Do they not require a digging/soil in the pen?

Hi Tweetypie, I'm glad its all going so well, they're very lucky hens to have landed up with you two.
So long as the nestboxes are lower than the perches in the coop, they should be OK once they get used to them. Hens like to sleep on the highest perch available, so the nestboxes need to be lower down to help prevent them sleeping (and pooing) in the boxes. I don't know how you can stop them laying on the floor, but you can just provide attractive soft bedding, then leave a couple of eggs in each box as a hint. If you don't want to use their own lovely eggs, just buy a cheap box and use those hard boiled for a bit, or you can buy artificial pot eggs from a farm shop. What bedding are you using in the nestboxes?
Yes they do need a dustbath in the run if you've got the floor covered with membrane or slabs. Just buy a really big plastic garden tub, at least 15" deep, and add dry garden soil and/or a bag of play sand from Homebase or similar. Needs to be in a dry area of the run, so your work getting it covered is good. It needs to be deep as they dig and roll around in the earth/sand then stand up and shake it all off, very funny to watch, but high sides catch the loose soil so it's not all lost over the sides of the dustbath. Imagine it's going to be a bath of water when selecting a tub or box - sort of chicken jacuzzi.
Slabs are OK for preventing mud from below, but are not porous so if they are not covered with bedding which you can poo pick, they will soon become very messy. If you then try to hose them down, the sludge won't have anywhere to go and will pile up at the sides and smell. If you can cover the slabs with bedding such as Aubiose the run will be much more comfortable for the hens, and easier to manage for you, as regular poo picking is very easy and makes good compost.

Me again. I have straw in the nest boxes and on the first day one of them laid an egg in there and then again in the afternoon (a soft egg),the other hen laid an egg on the floor that same day. They both lay their egg in the same "nest" on the floor. The coop was one of those flat packed styles and seems really good. The nestbox is lower than the perch by at least 5 inches, but hubbie is going to adapt and lower it closer to floor level to encourage them to go in. He seems to think its a height problem as they are fairly big hens. I think I will give that aubiose bedding a try aswell. We currently use dust extracted sawdust on the coop floor.

The pen that it attached to the coop is the part with some slabs resting on soil (which I need to change) and the additional run, which you can't see in the photo as it is not finished, is the run which has all that soil and grass nearthe big tree. I have temporarily fenced it off until hubbie has finished the fence. It means they have a freedom to go in and out when they want and then at night they go in the enclosed run and coop and are safe from predators (hopefully).

I want to ensure they have everything they need. They are a delight to have. I cannot believe I have only had them a week and every day they give me an egg each!

I attach a pic taken before "works" started, with a layout of where the external run will be, but I am using 4 foot fencing and roof is covered.

I did clip a wing of each of my first ex-batts when I got them, as I had the same concern as you. It proved not to be necessary though, so I've not done it since (except for medical reasons when a hen injured her wing & it was dragging on the ground last year).

I've had to coax the "girls" back occasionally when they've been gleaning in the field next door, but that's 'cos there are big gaps in the hedge... A rattle of the treats tub usually does the trick. Only once did one of my ex-batts have a bit of a flap (literally!) right next to the neighbour's fence & manage, to both her surprise and mine, to land on the wrong side of it! My neighbour was more than happy for me to go & pick her up.

I'm glad you're getting on so well with your girls. It looks as though they have a lovely garden to explore under your supervision.

Chickens are a girl's best friend (though diamonds would be nice too!)

You might consider removing the straw from the nestboxes and using Aubiose instead, or some other kind of bedding such as Hemcore or Cosybed. Or the paper bits from the office shredder are very good. Straw is not absorbent and so is hard to keep clean, nasty to poo pick if you get one in there, and also there's the possibility that an outbreak of redmite may lodge in the hollow stems. I'm also not too keen on sawdust in the coop, even if dust extracted, as you need to be very careful not to use anything in the coop which might cause respiratory problems, one of the biggest health problems for hens. If you have really secure inner run, it's good to leave the pophole door open all the time, summer and winter, to ensure full ventilation. You could use sheets of newspaper on the floor if you have any available, then just make a parcel of the top sheet every day when you clean them out. Maybe making the floor less cosy and comfortable might help with the nestbox problem. Then use Aubiose when you are able to get some. Here's the link to Aubiose stockists http://www.aubiose.co.uk/stockists.php
It's also available from various online outlets but if you can find a nearby supplier and collect it yourself it will be much cheaper without the postage.